mscroggs.co.uk
mscroggs.co.uk

subscribe

Puzzles

21 December

This year, I posted instructions for making a dodecahedron and a stellated rhombicuboctahedron.
To get today's number, multiply the number of modules needed to make a dodecahedron by half the number of tube maps used to make a stellated rhombicuboctahedron.

Show answer

Folding tube maps

Back in 2012, I posted instructions for folding a tetrahedron from tube maps. When tube maps are used, the sides of the tetrahedron are not quite equal. What ratio would the rectangular maps need to be in to give a regular tetrahedron?

Show answer & extension

Archive

Show me a random puzzle
 Most recent collections 

Advent calendar 2019

Sunday Afternoon Maths LXVII

Coloured weights
Not Roman numerals

Advent calendar 2018

Sunday Afternoon Maths LXVI

Cryptic crossnumber #2

List of all puzzles

Tags

probability coins unit fractions percentages spheres range number surds integration division money floors dice area sequences sum to infinity chalkdust crossnumber addition menace taxicab geometry indices factorials averages parabolas arrows means clocks quadratics digital clocks scales dodecagons algebra perimeter proportion logic mean cryptic crossnumbers squares multiplication sums wordplay graphs polygons square numbers tiling angles geometry triangles crossnumber pascal's triangle advent prime numbers elections dominos partitions trigonometry balancing palindromes shape ave circles rectangles chess differentiation routes symmetry perfect numbers rugby colouring 2d shapes people maths ellipses star numbers multiples remainders planes integers digits shapes sport complex numbers cryptic clues folding tube maps time volume crosswords cards speed games christmas the only crossnumber gerrymandering functions fractions calculus products probabilty 3d shapes dates grids coordinates odd numbers books numbers doubling cube numbers triangle numbers irreducible numbers chocolate crossnumbers median lines hexagons regular shapes square roots bases factors

Archive

Show me a random puzzle
▼ show ▼
© Matthew Scroggs 2012–2020